With Pickett and Jolly gone, the D lineman are: Raji (couldn't sniff an important deal in FA), Daniels, Jones, Boyd, Guion, Worthy. That's not exactly murderer's row.
With Pickett, Jolly and Wilson, you had major run stoppers but no pass rush. Its not just Brad Jones versus a superstar D lineman leaving the field for Casey Hayward. Its much more about mixing and matching. They need someone to step up and create a problem for the offense, then you have room to force teams to do things they do not wish to do. Daniels stepped up big, they need one more.